As light emitting materials of high molecular weight to be used in light emitting devices, copolymers are investigated, and for example, there is disclosed a copolymer containing a repeating unit, N,N-diphenyl-N-diyl-amino group or tetraphenylphenylenediaminediyl group and a repeating unit, fluorene-diyl group (Japanese Patent Application Laid-Open (JP-A) No. 2002-338665).
However, there is a problem that when the above-described known copolymer is used as a light emitting material of a light emitting device, the performances of the light emitting device are not necessarily sufficient.